williams



Jan. 31, 1956 R. w. WILLIAMS 2,733,105

FLUID OPERATED AIR EXHAUSTER Filed April 7, 1951 2 Sheets-Sheet l (D g 9- m '2 g T q I I I j I; St L f i L l l I Q cd I I 8 3 9% RAYIN\VIV.EN JI? RLZIAMS ATTORNEYS R- W. WILLIAMS FLUID OPERATED AIR EXHAUSTER Jan. 31, 1956 2 Sheets-Sheet 2 Filed April 7, 1951 INVENTORI RAY W. WILLIAMS ATTORNEYS:

United States Patent FLUID OPERATED AIR EXHAUSTER Ray W. Williams, Blue Island, 111,, assignor to United Conveyor Corporation, a corporation of Illinois Application April 7, 1951, Serial No. 219,781

11 Claims. (Cl. 30225) This invention relates to an improved fluid jet operated air exhauster, and in particular, it relates to such an air exhauster in which the combining tube is formed of heavy molded rubber or other resilient material and is provided with metal reinforcing members.

Fluid operated air exhausters ordinarily employ either steam or water jets, and are commonly used to operate pneumatic conveyors. In conveying chemicals and dust or ash pneumatically with a water jet, or with steam under conditions to cause condensation, the mist of water from the jet moistens the surface of the combining tube so that some of the conveyed material adheres to the tube and ultimately chokes it. For convenience such a jet will be referred to herein as a wet jet, to distinguish from a jet in which the steam is sufficiently superheated to avoid condensation at the prevailing temperature in the combining tube. This eifect is particularly diflicult to cope with in installations for the handling of certain types of ash, notably lignite ash. In handling lignite ash with a wet jet, the conveyor system may have to be taken down as often as once a day to clean the combining tube, and there are few installations which do not require cleaning at least once a week.

The present invention overcomes the foregoing difiiculty by substituting for the usual steel or cast iron combining tube a tube which is molded of rubber, or is formed of other resilient material, and has spaced steel reinforcing members molded into the rubber.

Any vapor jet is very noisy, which indicates that there is substantial vibration produced by the operation of the jet. This vibration has no substantial effect on the conventional rigid metal combining tube. However, the rubber combining tube picks up the vibration due to its flexibility, and when the jet is in operation the entire tube vibrates, or flexes, constantly so that no material can adhere to the inside of the tube. Accordingly, the conveyor system need not be disassembled to clean the exhauster. The rigid reinforcing members are necessary to prevent collapse of the tube due to the pressure reduction inside the tube when the exhauster is operating.

The principal object of this invention is, therefore, to provide a wet jet air exhauster for use in a pneumatic conveyor which avoids the necessity of disassembling the exhauster to clean the combining tube.

A further object is to provide an air exhauster in which the combining tube is of inexpensive and rugged construction, and avoids the disadvantages of metal combining tubes.

The invention is illustrated in a preferred embodiment and an alternative embodiment in the accompanying drawings in which Fig. 1 is a central vertical sectional view of a wet jet air exhauster equipped with a preferred form of combining tube, parts of the combining tube assembly being shown partially in section; and Fig. 2 is a fragmentary sectional view of a device to show an alternative form of combining tube.

Referring to the drawings in greater detail, and to 2,733,105 Patented Jan. 31, 1956 2 Fig. 1 in particular, the device comprises generally a nozzle assembly A and a combining tube assembly B which is the subject of the invention.

The nozzle assembly A consists of a nozzle section 10 which is flanged as seen at 11 to accommodate bolts 12 by which it may be fastened into a conduit. An opening in the top of the nozzle sectionlt) is surrounded by a gasket 13 to form a seal between the opening and a nozzle holder support 14 which is firmly secured to the nozzle section by means of bolts 15. A pipe 16 extends through the nozzle holder support and has at its inner end a nozzle holder 17 which has a nozzle 18 in its forward face. The pipe 16 is connected by appropriate unions to a fluid line 19 through which water or steam may be supplied from a fluid source (not shown) to the, nozzle 18, The nozzle section 10 tapers toward its forward end, which is centrally apertured and has an annular seat 20 surrounding the aperture to receive one end of the combining tube assembly B. Overlying the annular seat 20 is a gasket 21 against which an apertured frame member 22 of the combining tube assembly B is held in sealing engagement by means of bolts 23 and nuts 24, the aperture in the frame member being in register with the aperture at the front of the nozzle section 10.

The combining tube assembly comprises the apertured frame member 22 and a second apertured frame member 25 which is retained in spaced relation with respect to the frame member 22 by means of a plurality of tubular spacer members 26. A combining tube 27 is provided at its ends with flanges 28 and 29 which lie, respectively, against the frame members 22 and 25. Each of the flanges 28 and 29 is firmly clamped to the adjacent frame member by means of two piece flange clamps 30 and 31 respectively, the flange clamp 30 being secured in place by the bolts 23 and nuts 24 which hold the combining tube assembly on the face of the nozzle section 10. The flange clamp 31 is held in place by bolts 32 and nuts 33.

The combining tube 27 conveniently is formed of heavy rubber, although other resilient material will function satisfactorily and is molded with a plurality of steel rings 34 in the body of the tube 27, the rings being disposed in parallel planes which are perpendicular to the bore of the tube. It will be observed from the drawing that the combining tube varies in cross section so as to give. the usual Venturi construction, decreasing gradually in cross section from its mouth 35 to a point 36 spaced a short distance from the mouth. From the point 36 to a point 37 the tube diameter is constant, and from the point 3'7 to the discharge orifice 33 the combining tube flares gradually and as the tube flares the metal rings are spaced farther apart.

in a commercial installation which has been in experimental operation for some months, the combining tube is 28 /2 inches long and is formed of /5 inch molded rubber of #30 to #40 durometer. The steel reinforcing rings are 22 in number and are formed of inch diameter wire. Thus, the total space occupied by all the reinforcing rings is about of the total length of the tube. The first 11 inches of the tube from its mouth 35 contains 12 evenly spaced reinforcing rings 34, and from the twelfth ring to the twenty-second ring the space between rings increases A; inch for each successive pair. The first ring is at the line of the flange 28, and the diameter of the combining tube decreases steadily for the first 6 inches from about 6% inches at the mouth to about 4 7 inchesat the point 36. The diameter remains constant from point 36 to point 37 (a distance of 5 inches); and the inside diameter of the tube then increases uniformly to a maximum inside diameter of about 7 /2 inches at the outlet orifice 38.

Fig. 2 shows a modified form of combining tube assembly B, which is secured to a nozzle assembly A in the same fashion as the preferred assembly B. The elements of the combining tube assembly B are like those of the assembly B except for the construction of the combining tube itself; and the shape of this tube, which is designated by the reference numeral 127, is identical with that of the preferred form of tube 27. The tube 127 is molded of rubber and has a plurality of longitudinal ribs 128 molded into it, the ribs 128 being held in position by a plurality of rings 129 and 129a which preferably surround the ribs 128 and are secured to them.

The modified combining tube 127 is characterized by an ability to vibrate, similar to that of the tube 27, and it is prevented from collapsing by the reinforcing ribs 128 and rings 129, in particular by the two rings 129a which are located in the vicinity of the smallest part of the tube.

The foregoing detailed description is given for clearness of understanding only and no unnecessary limitations should be understood therefrom, as modifications will be obvious to those skilled in the art.

I claim:

1. In a wet jet air exhauster wherein the combining tube is subjected to substantially constant negative pressure, a combining tube of flexible material which would normally collapse during operation due to the negative pressure, said tube having a portion of minimum diameter intermediate its ends and flaring gradually from said portion toward both ends, and said tube being provided with rigid reinforcing means which are so positioned and arranged as to reinforce said tube against collapse during operation while permitting the tube to retain suflicient of its inherent flexibility to vibrate and prevent material from adhering to its inner surface.

2. In a wet jet air exhauster wherein the combining tube is subjected to substantially constant negative pressure, a combining tube of molded rubber which would normally collapse during operation due to the negative pressure, said tube having a portion of minimum diameter intermediate its ends and flaring gradually from said portion toward both ends, and said tube being provided with rigid reinforcing means which are so positioned and arranged as to reinforce said tube against collapse during operation while permitting-the tube to retain sufficient of its inherent flexibility to vibrate and prevent material from adhering to its inner surface.

3. In a wet jet air exhauster wherein the combining tube is subjected to substantially constant negative pressure, a combining tube of flexible material which would normally collapse during operation due to the negative pressure, said tube having a portion of minimum diameter intermediate its ends and flaring gradually from said portion toward both ends, and said tube being provided with a plurality of spaced reinforcing members which are so positioned and arranged as to reinforce said tube against collapse during operation while permitting the tube to retain suflicient of its inherent flexibility to vibrate and prevent material from adhering to its inner surface.

4. The device of claim 3 in which the reinforcing mem bers comprise spaced rigid rings lying in parallel planes perpendicular to the bore of the tube.

5. The device of claim 3 in which the reinforcing mem' bers comprise a plurality of spaced longitudinal ribs, and a plurality of retaining rings secured to the ribs.

6. The device of claim 5 in which at least two rings are located in the vicinity of that portion of the tube which is of minimum diameter.

7. The device of claim 3 which is formed of molded rubber, and in which the reinforcing members are metal rings molded into the rubber.

8. The device of claim 3 in which the reinforcing members comprise a series of closely spaced metal reinforcing rings lying in parallel planes perpendicular to the bore of the tube, and extending substantially from end to end of said tube.

9. In a wet jet air exhauster, in combination, a pair of spaced, apertured frame members, a plurality of rigid spacer elements connecting said members, a combining tube having flanges at its ends by which it is bolted to the frame members with its bore aligned with the apertures, said combining tube being formed of flexible material which would normally collapse when subjected to negative pressure, said tube being provided with rigid reinforcing means which are so positioned and arranged as to reinforce said tube against collapse during operation while permitting the tube to retain suflicient of its inherent flexibility to vibrate and prevent material from adhering to its inner surface.

10. The device of claim 9 in which the combining tube is thick, molded rubber and the reinforcing means consists of a series of spaced metal rings lying in parallel planes perpendicular to the bore of the tube and extending substantially from end to end of the tube.

11. The combining tube assembly of claim 9 in which the reinforcing means comprises a plurality of spaced longitudinal ribs secured together by spaced retaining rings.

References Cited in the file of this patent UNITED STATES PATENTS 1,124,579 Ambursen Ian. 12, 1915 1,205,984 Forsyth Nov. 28, 1916 1,570,795 Tainton Jan. 26, 1926 2,107,084 Fletcher Feb. 1, 1938 2,374,249 Wadsworth Apr. 24, 1945 2,420,388 Thomas May 13, 1947 2,540,002 Mason Jan. 30, 1951 FOREIGN PATENTS 535,648 Great Britain Apr. 16, 1941 

